The present invention relates to a caster assembly and more particularly to a retractable caster for difficult-to-manage cases, crates and the like.
There has long been a problem with handling of large or heavy cases, crates and special materials, e.g. up to approximately 1,000 lbs to 1,300 lbs, without the aid of powered assistance, i.e. without forklifts, tow-motors, pallet movers, winches and the like. It may be necessary to handle such cases in conditions where such power tools are unavailable or there is not sufficient space for their use. Even where containers are relatively light, e.g. 150 lbs to 350 lbs, they may be too bulky for manual handling.
Currently, for military applications, air transport aircraft utilize a common roller system on a ramp for freight handling. Various types of containers and cargo are hand-loaded onto pallets, then placed on the rollers of the aircraft's lowered ramp, and winched inside where they are tied down securely. Such cargo may include palletized "battle boxes", medi-cases, ammunition boxes, projectile cases and other standard types of cargo in reusable containers. On the C-130 Hercules aircraft, for example, the roller system weighs approximately 1,700 lbs and takes away from cargo capacity. As well, in the military and in civilian industrial and commercial situations, many types of cargo including engines, transmissions and the like are transported in sealed containers. Until now, such containers have had to be moved by forklift, under ideal conditions, or else manually handled.
While it is known to fit conventional casters to the bottom of heavy objects to facilitate their moving, the usage of such casters has been extremely limited. If the object, such as a cargo container, will be frequently carried on an aircraft, truck, boat or the like, where it will be subjected to irregular and possible sudden motion, such casters have proven unsuitable as they must be removed during transit, or the container firmly tied down. Obviously there is not a problem with such casters on the bottom of heavy furniture which will not be frequently moved.
It is an object of the present invention to provide a type of caster which may, if required, be permanently secured to cases, crates, speciality boxes and the like which are used for transporting bulky or heavy cargo materials. It is a further object of the present invention to provide such a caster which may be fitted ion new containers or the like, or retro-fitted on old ones, and which will instantly facilitate the manual handling, without the aid of powered assistance, of such containers and the like.